opencv常用基本操作

安装opencv

在cmd中进入运行环境的script文件夹，利用pip install opencv-python，下载地址选择国内镜像地址。

解决cv2代码不提示的问题

修改cv2模块中的__init__.py文件内容，把原有的代码修改为：

1 import sys
2 import os
3 import importlib
4 os.environ["PATH"] += os.pathsep + os.path.dirname(os.path.realpath(__file__))
5 from .cv2 import *
6 globals().update(importlib.import_module(\'cv2.cv2\').__dict__)

opencv常用操作

 1 # -*- coding:utf-8 -*-
 2 # author:平手友梨奈ii
 3 # e-mail:1353593259@qq.com
 4 # datetime:2019/10/8 0008 22:31
 5 # filename:learncv2.py
 6 # software: PyCharm
 7 
 8 import cv2
 9 import numpy as np
10 
11 """
12     opencv主要用于图像的预处理，例如数据增强
13 """
14 
15 # 图片加载，灰度图显示，保存
16 img = cv2.imread(\'demo.jpg\')
17 # cv2.imshow(\'少女\', img)
18 img_grey = cv2.imread(\'demo.jpg\', flags=0)
19 # cv2.imshow(\'grey\', img_grey)
20 # cv2.waitKey(0)
21 cv2.imwrite(\'result1.jpg\', img_grey)
22 
23 # 图像显示窗口的创建与销毁
24 cv2.namedWindow(\'window\', flags=cv2.WINDOW_NORMAL)  # cv2.WINDOW_NORMAL创建一个大小可以调整的窗口
25 # cv2.imshow(\'window\', img)
26 # cv2.waitKey(0)
27 cv2.destroyWindow(\'window\')  # 删除窗口
28 # cv2.destroyAllWindows()  # 删除所有已经建立的窗口
29 
30 # 图片的基本信息
31 shape1 = img.shape
32 shape2 = img_grey.shape
33 print(shape1)  # (675, 1201, 3)
34 print(shape2)  # (675, 1201)
35 size1 = img.size
36 size2 = img_grey.size
37 print(size1)  # 2432025
38 print(size2)  # 810675
39 dtype = img.dtype
40 print(dtype)  # uint8 0-256
41 
42 img_zero = np.zeros(shape1, dtype=np.uint8)
43 # cv2.imshow(\'zeros\', img_zero)
44 # cv2.waitKey(0)
45 
46 # 访问图像中的像素
47 pixel = img[10, 10]
48 print(pixel)
49 img[10:100, 10:100] = [255, 0, 0]  # 注意，opencv访问通道的顺序是B,G,R
50 # cv2.imshow(\'img_modif\', img)
51 # cv2.waitKey(0)
52 
53 # 像素通道的分离split与合并merge
54 B, G, R = cv2.split(img)
55 # cv2.imshow(\'Blue\', B)
56 # cv2.imshow(\'Green\', G)
57 # cv2.imshow(\'Red\', R)
58 channel_merge = cv2.merge([B, G, R])  # 将其融合为三通道图像
59 print(channel_merge.shape)
60 # cv2.imshow(\'merge\', channel_merge)
61 # cv2.waitKey(0)
62 
63 # 给图片上加上文字说明
64 cv2.putText(img, \'hirate yurina\', org=(100, 100), fontFace=cv2.FONT_HERSHEY_SIMPLEX,
65             fontScale=1, color=(0, 0, 255))
66 # cv2.imshow(\'text\', img)
67 # cv2.waitKey(0)
68 
69 # t图像的缩放
70 resize = cv2.resize(img, (200, 400))
71 cv2.imshow(\'resize\', resize)
72 cv2.waitKey(0)